Xiaowei Yang

Summary

Affiliation: University of California
Country: USA

Publications

  1. ncbi request reprint Markov transition models for binary repeated measures with ignorable and nonignorable missing values
    - Xiaowei Yang
    Division of Biostatistics, Department of Public Health Sciences, University of California, Davis, CA 95616, USA
    Stat Methods Med Res 16:347-64. 2007
  2. pmc Imputation-based strategies for clinical trial longitudinal data with nonignorable missing values
    Xiaowei Yang
    Division of Biostatistics, School of Medicine, University of California, Med Sci 1 C, Suite 200, Davis, CA 95616, USA
    Stat Med 27:2826-49. 2008
  3. ncbi request reprint Functional regression analysis using an F test for longitudinal data with large numbers of repeated measures
    Xiaowei Yang
    Department of Public Health Sciences, Division of Biostatistics, University of California, Davis, CA 95616, USA
    Stat Med 26:1552-66. 2007
  4. ncbi request reprint Hypothesis testing in functional linear regression models with Neyman's truncation and wavelet thresholding for longitudinal data
    Xiaowei Yang
    Division of Biostatistics, Department of Public Health Sciences, School of Medicine, University of California, Davis, CA 95616, USA
    Stat Med 27:845-63. 2008
  5. doi request reprint A quasi F-test for functional linear models with functional covariates and its application to longitudinal data
    Hongquan Xu
    Department of Statistics, University of California, Los Angeles, CA 90095, USA
    Stat Med 30:2842-53. 2011
  6. ncbi request reprint Assessing missing data assumptions in longitudinal studies: an example using a smoking cessation trial
    Xiaowei Yang
    BayesSoft Inc, 11075 Santa Monica Blud, Suite 200, Los Angeles, CA 90025, USA
    Drug Alcohol Depend 77:213-25. 2005
  7. ncbi request reprint Imputation and variable selection in linear regression models with missing covariates
    Xiaowei Yang
    Department of Biostatistics, University of California, 11075 Santa Monica Boulevard, Suite 200, Los Angeles, California 90095 1772, USA
    Biometrics 61:498-506. 2005
  8. pmc Correlations of gene expression with blood lead levels in children with autism compared to typically developing controls
    Yingfang Tian
    Department of Neurology, University of California at Davis, Sacramento, CA 95817, USA
    Neurotox Res 19:1-13. 2011
  9. pmc Prevalence of viremia and oral shedding of rhesus rhadinovirus and retroperitoneal fibromatosis herpesvirus in large age-structured breeding groups of rhesus macaques (Macaca mulatta)
    Jessica A White
    California National Primate Research Center, University of California, Davis, California, USA
    Comp Med 59:383-90. 2009
  10. pmc Correlations between gene expression and mercury levels in blood of boys with and without autism
    Boryana Stamova
    Department of Neurology, University of California at Davis Medical Center, Sacramento, CA 95817, USA
    Neurotox Res 19:31-48. 2011

Research Grants

Collaborators

Detail Information

Publications21

  1. ncbi request reprint Markov transition models for binary repeated measures with ignorable and nonignorable missing values
    - Xiaowei Yang
    Division of Biostatistics, Department of Public Health Sciences, University of California, Davis, CA 95616, USA
    Stat Methods Med Res 16:347-64. 2007
    ..Markov transition models provide a novel reconceptualization of treatment outcomes, offering both intuitive statistical values and relevant clinical insights...
  2. pmc Imputation-based strategies for clinical trial longitudinal data with nonignorable missing values
    Xiaowei Yang
    Division of Biostatistics, School of Medicine, University of California, Med Sci 1 C, Suite 200, Davis, CA 95616, USA
    Stat Med 27:2826-49. 2008
    ..For illustration, the strategies were applied to a data set with continuous repeated measures from a smoking cessation clinical trial...
  3. ncbi request reprint Functional regression analysis using an F test for longitudinal data with large numbers of repeated measures
    Xiaowei Yang
    Department of Public Health Sciences, Division of Biostatistics, University of California, Davis, CA 95616, USA
    Stat Med 26:1552-66. 2007
    ..A simulation study is also conducted under the condition of the smoking data to investigate the statistical power for the F test, Wilks' likelihood ratio test, and the linear mixed-effects model using AIC...
  4. ncbi request reprint Hypothesis testing in functional linear regression models with Neyman's truncation and wavelet thresholding for longitudinal data
    Xiaowei Yang
    Division of Biostatistics, Department of Public Health Sciences, School of Medicine, University of California, Davis, CA 95616, USA
    Stat Med 27:845-63. 2008
    ..Since a FLRM can be viewed as a natural extension of the traditional multiple linear regression model, the development of this model and computational tools should enhance the capacity of medical statistics for longitudinal data...
  5. doi request reprint A quasi F-test for functional linear models with functional covariates and its application to longitudinal data
    Hongquan Xu
    Department of Statistics, University of California, Los Angeles, CA 90095, USA
    Stat Med 30:2842-53. 2011
    ..For illustration, we apply the proposed procedure to a longitudinal depression data set with repeatedly measured methamphetamine use as a predictor. We conduct a simulation study to assess the size and the power of the test...
  6. ncbi request reprint Assessing missing data assumptions in longitudinal studies: an example using a smoking cessation trial
    Xiaowei Yang
    BayesSoft Inc, 11075 Santa Monica Blud, Suite 200, Los Angeles, CA 90025, USA
    Drug Alcohol Depend 77:213-25. 2005
    ..A carbon monoxide longitudinal data set in a smoking cessation study is used for illustration...
  7. ncbi request reprint Imputation and variable selection in linear regression models with missing covariates
    Xiaowei Yang
    Department of Biostatistics, University of California, 11075 Santa Monica Boulevard, Suite 200, Los Angeles, California 90095 1772, USA
    Biometrics 61:498-506. 2005
    ..Simulation studies show that both ITS and SIAS outperform complete-case analysis with stepwise variable selection and that SIAS slightly outperforms ITS...
  8. pmc Correlations of gene expression with blood lead levels in children with autism compared to typically developing controls
    Yingfang Tian
    Department of Neurology, University of California at Davis, Sacramento, CA 95817, USA
    Neurotox Res 19:1-13. 2011
    ..We postulate that this may relate to the underlying genetic differences between the two groups, though other explanations cannot be excluded...
  9. pmc Prevalence of viremia and oral shedding of rhesus rhadinovirus and retroperitoneal fibromatosis herpesvirus in large age-structured breeding groups of rhesus macaques (Macaca mulatta)
    Jessica A White
    California National Primate Research Center, University of California, Davis, California, USA
    Comp Med 59:383-90. 2009
    ..Both RRV and RFHV are highly endemic in socially housed breeding colonies of rhesus macaques, and their patterns of infection are similar to that for the betaherpesvirus rhesus cytomegalovirus...
  10. pmc Correlations between gene expression and mercury levels in blood of boys with and without autism
    Boryana Stamova
    Department of Neurology, University of California at Davis Medical Center, Sacramento, CA 95817, USA
    Neurotox Res 19:31-48. 2011
    ..These findings might suggest different genetic transcriptional programs associated with mercury in AU compared to TD children...
  11. ncbi request reprint The relation of acculturation to overweight, obesity, pre-diabetes and diabetes among U.S. Mexican-American women and men
    Lorena Garcia
    Department of Public Health Sciences, University of California, Davis School of Medicine, 95616, USA
    Ethn Dis 22:58-64. 2012
    ..To estimate and compare the prevalences of overweight, obesity, pre-diabetes and diabetes among a nationally representative sample of Mexican-American, non-Latino white and black adults, and by acculturation for Mexican-Americans...
  12. pmc Sustained reductions in drug use and depression symptoms from treatment for drug abuse in methamphetamine-dependent gay and bisexual men
    James A Peck
    UCLA Integrated Substance Abuse Programs, 11075 Santa Monica Boulevard, Suite 200, Los Angeles, CA 90025, USA
    J Urban Health 82:i100-8. 2005
    ..Findings show that behavioral methamphetamine abuse treatment yields reductions in methamphetamine use and concomitant depressive symptom ratings that are sustained to 1 year after treatment entry...
  13. pmc Validation of a body condition scoring system in rhesus macaques (Macaca mulatta): assessment of body composition by using dual-energy X-ray absorptiometry
    Laura Summers
    California National Primate Research Center, University of California, Davis, CA, USA
    J Am Assoc Lab Anim Sci 51:88-93. 2012
    ..0-to-5.0 BCS range. Absolute body fat in animals with BCS of 1.0 or 1.5 may be too low for accurate assessment by DEXA...
  14. pmc Increased rate of amygdala growth in children aged 2 to 4 years with autism spectrum disorders: a longitudinal study
    Christine Wu Nordahl
    MIND Institute, University of California, Davis, School of Medicine, Sacramento, CA 95817, USA
    Arch Gen Psychiatry 69:53-61. 2012
    ..Precocious amygdala enlargement is commonly observed in young children with autism. However, the age at which abnormal amygdala enlargement begins and the relative growth trajectories of the amygdala and total brain remain unclear...
  15. ncbi request reprint Evolution of hemodialysis access resistance: a longitudinal 5-year model using functional principal components analysis
    Andrew I Chin
    Department of Internal Medicine, Division of Nephrology, University of California, Davis School of Medicine, 4150 V Street, Suite 3500, Sacramento, CA, USA
    Int J Artif Organs 32:864-71. 2009
    ..To describe these changes, we applied a novel statistical methodology of functional principal component (FPC) analysis...
  16. pmc Longitudinal patterns of viremia and oral shedding of rhesus rhadinovirus and retroperitoneal fibromatosis herpesviruses in age-structured captive breeding populations of rhesus Macaques (Macaca mulatta)
    Jessica A White
    California National Primate Research Center, School of Medicine, University of California, Davis, California, Koelle Lab, University of Washington, Seattle, Washington, USA
    Comp Med 61:60-70. 2011
    ....
  17. ncbi request reprint A random-effects Markov transition model for Poisson-distributed repeated measures with non-ignorable missing values
    Jinhui Li
    UCLA Department of Statistics, PO Box 951554, Los Angeles, CA 90095 1554, USA
    Stat Med 26:2519-32. 2007
    ..The method is demonstrated using both simulated data sets and a practical data set from a smoking cessation clinical trial...
  18. ncbi request reprint Randomized placebo-controlled trial of baclofen for cocaine dependence: preliminary effects for individuals with chronic patterns of cocaine use
    Steven Shoptaw
    UCLA Integrated Substance Abuse Program, Los Angeles, Calif 90025, USA
    J Clin Psychiatry 64:1440-8. 2003
    ..This screening trial evaluated whether the GABAB agonist baclofen demonstrated sufficient clinical efficacy to recommend an adequately powered trial of the medication as a pharmacotherapy for cocaine dependence...
  19. ncbi request reprint Participants receiving dehydroepiandrosterone during treatment for cocaine dependence show high rates of cocaine use in a placebo-controlled pilot study
    Steve Shoptaw
    Friends Research Institute, Los Angeles, CA, USA
    Exp Clin Psychopharmacol 12:126-35. 2004
    ..No differences were detected between conditions for cocaine craving or adverse experiences. High levels of medication compliance were documented. Results argue against using high doses of DHEA as a pharmacotherapy for cocaine dependence...
  20. ncbi request reprint Randomized, placebo-controlled trial of baclofen and gabapentin for the treatment of methamphetamine dependence
    Keith G Heinzerling
    Integrated Substance Abuse Programs, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA 90024, USA
    Drug Alcohol Depend 85:177-84. 2006
    ..To conduct a 16-week, randomized, placebo-controlled, double-blind trial of two GABAergic medications, baclofen (20 mg tid) and gabapentin (800 mg tid), for the treatment of methamphetamine dependence...
  21. ncbi request reprint Smoking cessation in methadone maintenance
    Steve Shoptaw
    Friends Research Institute, Los Angeles, CA, UCLA, Department of Psychiatry, Los Angeles, CA 90025, USA
    Addiction 97:1317-28; discussion 1325. 2002
    ..To evaluate relapse prevention (relapse prevention) and contingency management (contingency management) for optimizing smoking cessation outcomes using nicotine replacement therapy for methadone-maintained tobacco smokers...

Research Grants1

  1. Transition Model for Incomplete Longitudinal Binary Data
    Xiaowei Yang; Fiscal Year: 2003
    ..In MLM approach, status of missingness is treated as a third category to extend the repeated measures into three-category ones. ..